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| Type |
Symposium |
| Area |
Recent Trends in Organometallic Chemistry |
| Room No. |
Room 211+212+213 |
| Time |
FRI 15:40-: |
| Code |
INOR2-4 |
| Subject |
Photosensitization Effects of Ir(III) Complexes in Selective Reduction of CO2 by Re(I)-Complex-Anchored TiO2 Hybrid Catalyst |
| Authors |
Ho-Jin Son
Department of Advanced Materials Chemistry, Korea University, Sejong, Korea |
| Abstract |
A series of cationic Ir(III) complexes ([Ir(btp)2(bpy-X2)]+ (Ir-X+: btp = (2-pyridyl)benzo[b]thiophen-3-yl; bpy-X2 = 4,4′-X2-2,2′-bipyridine (X = OMe, tBu, Me, H, and CN)) were applied as visible-light photosensitizer in solution to the selective CO2 reduction to CO in the presence of an electron donor (BIH) and a hybrid catalyst (TiO2/ReP) prepared by anchoring of Re(4,4’-Y2-bpy)(CO)3Cl (Y = CH2PO(OH)2) on TiO2 particles. Irradiation of the system in N,N-dimethylformamide (DMF) at >400 nm resulted in the successful reduction of CO2 to CO with efficiencies in the order X = tBu ~ Me > OMe > H; Ir-CN+ has no photosensitization effect. An interesting observation is that Ir-tBu+ and Ir-Me+ are less efficient than Ir-OMe+ at an early stage of the reaction but reveal persistent photosensitization behavior for a longer period of time unlike the latter. Comparable experiments showed that (1) the Ir-X+ sensitizers are commonly superior compared to Ru(bpy)32+, a widely used transition-metal photosensitizer and (2) the system comprising Ir-tBu+ and TiO2/ReP is much more efficient than a homogeneous-solution system using Ir-tBu+ and Re(4,4′-Y′2-bpy)(CO)3Cl (Y′ = CH2PO(OEt)2). Implications of the present observations and reaction mechanisms are discussed in detail. |
| E-mail |
hjson@korea.ac.kr |
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120th General Meeting of the KCS